Generally speaking, the major issues inherent to current amplification methods and system are the opposing requirements for ultra-broadband versus high power amplification. Parametric amplification is currently realized either in a broadband, low gain arrangement referred to as type I amplification, or in a narrowband, high gain configuration referred to as type II amplification [Cerullo03]. Due to phase matching restrictions, a compromise between high amplification factors and reduced amplified bandwidth has to be accepted.
High power amplification of ultra-broadband laser pulses is currently achieved using Optical Parametric Chirped Pulse Amplification (OPCPA) [Dubietis06] using Type I crystals or periodically poled crystals to meet conditions for quasi phase matching, respectively. On the other hand, Type I amplification in a non-collinear geometry (NOPA) can be achieved over broader bandwidths than type II at the expense of lower pulse energies. In both cases the maximum amplification bandwidth is limited. Although OPCPA is a promising approach, capable to support 2 cycle pulses with 740 μJ, this method requires development of new pump sources and its temporal pulse contrast is impaired by significant superfluorescence back ground [Gu09].
In current parametric amplification methods, amplification is carried out in time domain where all spectral components are present at once or in time sequentially in case of OPCPA.
There is still a need in the art for a method and a system for high power amplification of ultra-broadband few-cycle laser pulses in the framework of parametric amplification.